Rotary switch actuator



June 15, 1965 usc 3,188,881

ROTARY SWITCH ACTUATOR Filed Dec. 29, 1961 I 2 Sheets-Sheet 2 INVENTOR. ROBERT A. PUSCH,

A TTORN E Y.

June 15, 1965 R. A. PUSCH 3,188,881

ROTARY SWITCH ACTUATOR Filed Dec. 29, 1961 2 Sheets-Sheet 1 IN VENTOR. ROBERT A. PuscH,

ATTORNEY.

United States Patent 3,188,881 ROTARY SWHTCH ACTUATOR Robert A. Hirsch, Le Roy, 111., assignor to General Electric Company, a corporation of New York Filed Dec. 29, 1961, Ser. No. 163,274 Claims. (Cl. 74-604) This invention relates to switch actuators and has particular relation to switch actuators of the rotary type.

Switch actuators of the rotary type have heretofore been constructed to include a rotatable shaft having thereon means, such as a cam, for actuating a switch operator, and a manually actuatable element attached to the shaft for effecting rotation thereof. Rotation of the shaft is transmitted through the switch operator to operate one or more switch contacts. Such switch actuators have heretofore included means for controlling the retary position of the shaft. For example, rotary switch actuators have heretofore included means for providing a spring-return action when the shaft is rotated in either direction from a neutral position and released. Also, means have previously been provided to maintain the shaft in either of two positions spaced from a neutral position when the shaft is rotated to such positions and released.

In many installations it is desirable to provide a rotary switch actuator including a manually rotatable element or turn button which is rotatable from a neutral position in opposite directions to a pair of operating positions, and to provide means for maintaining the turn button in one of the operating positions when released, and to provide a spring-return mechanism for returning the turn button to the neutral position when the button is rotated to the other of its operating positions and released. Such an actuator may be defined as a three-position, spring return, maintained rotary actuator.

It is therefore a primary object of the present invention to provide a novel and improved rotary switch actuator of the three position, spring return, maintained type which is of inexpensive and compact construction andwhich incorporates a minimum number of parts.

It is another object of the invention to provide a novel and improved rotary switch actuator including separate means for returning a rotatable shaft to a neutral position from a first operating position when the shaft is released and for maintaining the shaft in a second operating position when rotated from a neutral position with a minimum of undesirable interference between the separate means.

It is a further object of the invention to provide a rotary switch actuator including separate means for returning a rotatable shaft to a neutral position from a first operating position when the shaft is released and for maintaining the shaft in a second operating poistion when rotated from a neutral poistion, such separate means being designed to take up a minimum amount of space in dimensions extending both radially and axially of the shaft.

In carrying out the invention in one preferred form there is provided a rotary switch actuator including a shaft supported within a hollow base for rotation and carrying a cam for actuating a switch operating element. The shaft is connected to a rotatably mounted, manually actuatable turn button for rotation therewith from a neutral rest position in opposite directions to a pair of spaced operating positions. In order to provide a spring return function for returning the shaft from one of the operating positions to a neutral position when released, a

tension spring is provided which is wrapped around the shaft and having ends engaged respectively with a pair of axially spaced plates surrounding the shaft which have relative movement for one direction of rotation of the shaft to elongate the spring and provide the return function, and which have no relative movement for the other direction of rotation of the shaft in which the maintained function is desired. The maintained function is provided by means of a cam and leaf spring arrangement which are movable relative to each other in response to rotation of the shaft in the direction for which a maintained function is desired. The cam is preferably carried by the switch operating cam on the shaft and the leaf spring is supported by the base.

Other objects and advantages of the invention will become apparent from the following description taken in conjunction with the accompanying drawings in which,

FIG. 1 is a view in elevation with parts shown in section of a switch including a rotary switch actuator constructed in accordance with the teachings of the present invention;

FIG. 2 is a view in section taken along the line 2--2 of FIG. 1;

FIG. 3 is a view in section taken along the line 33 of FIG. 1;

FIG. 4 is an exploded view with parts shown in perspective of elements of the actuator;

FIG. 5 is a view in section taken along the line 55 of FIG. 3;

FIG. 6 is a view section showing an actuator of modified form with a different type of maintaining mechanism;

FIG. 7 is a view in bottom plan of the actuator of FIG. 6 with a part removed; and

FIG. 8 is a view in perspective of a part of the maintaining mechanism of the actuator of FIGS. 6 and 7.

Referring now to the drawing there is illustrated in FIG. 1 a switch structure including a rotary switch actuator 10 having secured thereto a contact block 11 which may be of the construction set forth in copending application S.N. 77,576, filed December 22, 1960 by R. A. Pusch et a1. and assignedto the assignee of the present invention, now Pat. No. 3,118,026, issued July 28, 1964. The actuator 10 includes a hollow base 12 having a central cavity 13 and having an upper end as viewed in FIG. 1 which is externally threaded at 14 to threadably engage internal threads on a ring 15. The base 12 includes an external annular flange 16 adapted to cooperate with the ring 15 to mount the actuator 10 and contact block 11 to a panel 17 which engages the lower surface of a spacer 17' between the panel 17 and the ring 15 and which also engages the upper one of a plurality of spacers 18 resting on the upper surface of the flange 16.

The actuator 10 includes a turn button 20 which is rotatably supported by the ring 15 and which includes an integral projection 21 extending through an upper opening of the ring 15 and containing a square socket 22 adapted to receive a square extension 23 formed on the upper end of a shaft 24. The button 20 is secured to the ring 15 by a C-shaped clamp 25 fit in a groove of the projection 21 and engaging the inner surface of the end wall of ring 15. The shaft 24 is mounted for rotation within the base by an internal flange 26 at the upper end of the base and by a centrally apertured washer 27 secured to the inner wall of the base adjacent the lower end of the base. A sealing gasket 28 is positioned on the flange 26 in the space between the upper end of the shaft 24 and the inner wall of the base.

In order to effect operation of switches in the block 11 there is provided a cam 30 secured to the lower end of the shaft 24 by means of a screw 31. The cam 30 rotates in response to rotation of the shaft 24 and includes a plurality of cam surfaces upon which rests a 3 vertically movable actuator 32 as viewed in FIG. .1' adapted to reciprocate to move contacts carried thereby into and out of engagement with fixed contacts within the block 11 in response to rotation of the cam30. Details of the contact arrangement within the block 11 and fur-. 'ther details of the configuration of thecam30 may be found in the aforementioned Puschiet a1; application. According to the present invention means are provided to effect a spring-return function when the shaft shaft'is rotated in the direction for whichthe springreturn function is desired, and be inoperative or ineffecdirections is limited by' engagement of the tab 47 with radially extending surfaces 27:; and 27b of the washer 27.

The maintaining function is effective when the button 20 is rotated in the clockwise direction. This function is effected by means of a detent mechanism including engageable parts on the base 12 and on the cam 30 which latchingly engage in responseto rotation of the cam 30 relative to the base 12 in the clockwise direction to the second operating position/In one embodiment of the "invention shown in FIGS. 3 and 5 the detent mechanism includes,v a generally flat leaf spring 60 secured to the undersurface of the washer 27'as.by weldingindicated at the point-61. The spring 60 includes a downwardlyextending projection 62 adaptedto engageablycooperate five when the'shaft is rotated in the,opposite direction for which the maintained functionis desired. The means for providing the spring-return function, will iiow' be" described with particular reference toFIGS. 1,2 and 4.

As shown in FIGS. 1, 2 and 4, a tension spring of coil configuration is wrapped about, the shaft 24-and has its ends engaged respectively by tabs or hooks 36 and 37 formed ona pair of axially spacedcentrally'apertured rings or disks 38 and 39. The, di-sks38 and 39 include respectively confronting collars 40 and 41 which fit ,withinta tube 42 F surrounding the shaft 24 and the assembly including the spring, disks and the tube is positioned in the space between the washer 27 and'the with an upwardly-projecting triangular cross-section extension'63on the upper surface of the switch operating cam 30. The free end 64 of 'the'spring 60 islocated beneath a slot 65 formed in the washer 27 andwhich serves topermit upward movement of the spring 60 in response to engagement 'of the projection 62 thereof with the extension 63; t v v p 7 'In operation, when the button ,20 is rotated in a clockwise direction as viewed in :FIGS. .3 and 4, the extension 63 on the, cam 30is riotatedini a corresponding direction relative to the washer 27: and the sprin'g 60 secured thereto.

As the button 20 approaches the second operating position, the gradually sloped leading surface of the extension 63 engages theprojection 62 ,ofthe spring 60 to elevate the flange 26 of the base. The disk 39 includes a radially extending projection 45, adapted to engage one side of, p avertically extending ridge 46 formed on the'inner wall of, the base. The projection is also arranged to -be contacted at its side by an upwardly extending tab 47 on the cam 39 in response to rotation'of the button; 20 g I I past the projection 62 and effect return ofthe button and and the cam 30 in the clockwisedirec-tion indicated by the arrows CW as viewed in FIG. 4. Theshaft 24 includes an annular shoulder 48 beneath and overlapping the flange 26 and having a downwardly projecting tab 49 adapted to engage the lateral surface of a projection 50. of the disk 38 in response to rotation of the button 20'and the cam 30 in a t o lnterclockwise direction as indicated by the arrows CCW in FIG. 4.

Inoperation it willbe initially assumed that the'button' the cam 30 to the neutral position.

20 is at its neutral rest position shown in.FIG. 1. In a this position the parts are arranged suchthat the. tab 49 t on the shaft 24 engages the projection .50' of the disk '38 When the bu'tton2 0 is rotated in the counterclockwise direction the tab .49 effects movement of the disk. 38 in a corresponding direction by. engagement of the projection 50, and the spring 35 is extended due to thefact that the projection 45. of thedisk 39engages the ridge 46 and is between the'disks 38 and 39 occurs tending to extend the spring 35.for counterclockwise rotation of theibutton 20."

disk 39 to rotate disk 39 in the clockwise direction. The

projection '50 of disk 38,: however, is not long enough to contact the ridge 46 and therefore disk 38 rotates with spring, and continued rotation of the button 20 results in passage of the apex'of the extension 63 by the lowermost part of the projection 62 and downward movement of the spring intouengag'ement ,with theseverely sloped trailing surface of the extension 63. With this arrangement the'button 20 and the cam 30 are held in such position When the button 20 is released, and acertain positive force acting on the button 20 in the counterclockwise directionis necessary in order to move the extension 63 As previously described herein, during rotation of the button 20 in the clockwise direction there is no elongation of the spring 35. Also, there isvno appreciable friction between the projection 62 of the spring 60 and the upper surface of the cam30. V p

Other arrangements of the detent mechanism'are possible. For example, the spring 60 may be formed with an extended free end and be secured at both, of its ends to the washer.27. ,Thisar'rangement gives an increase in the detenting force over that wherein the spring is secured only at its right hand end a s viewed in FIG.'5'. 1

FIGS. 6,' 7,, and 8 illustrate adifierentqarrangement of the detent mechanism forp'roviding the maintained stopped against rotation; Therefore a relativemovement 1 disk 39.- For this condition then there is no relative movement between the disks 38 and 39 and therefore, there is no elongation of the spring 35 and no spring Another arrangement for preventing relative rotation be tween disks 38 and 39 for clockwise rotation of button 20 would consist of removing tab 47 from cam 30. Rota tion of button 20 in the clockwise and counterclockwise '70 return function for clockwise rotation of the button 20.. a

function. Similar parts in the devicesof FIGS. 6 and 1 are represented by the'same reference numerals. In the arrangement of FIGSJ-6-8 a' places the spring 60 and is positioned to surround the pecurved split spring reriphery of thecam 30. Thespring 70 includes a pair of spaced ends 71 and apair of'diametrically-oppos'ed slots 72 which engagerespectivelya projection 73formed on the washer 27 and a ridge 74on the inner wall of the base. Spring 70 includes a projection 75 adjacent one of its ends and extending radially inwardly thereof to engage "an outwardly extending extension 76 formed on the periphery ofrthe cam 30. The operation of the arrangement shown at FIGS; 6 and '7 issimilar to that shown in FIGS. 3 and 5 and need'not be described in detail. a

7 It is thus seen that a rotary switch actuator is provided including unique means for eifecting a spring return function for one direction of rotation of the button 20 from a neutral 'position, and for effecting a -rnaintained function for'rotation of the button 20 in the opposite direction. The arrangement is such that'the. mechanisms for providing the two functions do not interfere with each other and the spring return function is rendered ineffective for rotation of the button 20 in the maintained direction. Also, the two mechanisms take up a very small space in the actuator, include a minimum number of parts, and are inexpensive to manufacture, all of which results in a very etficient, inexpensive and compact rotary switch actuator.

Although the invention has been described with reference to certain specific embodiments thereof, numerous modifications are possible, and it is desired to cover all modifications falling within the spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In a rotary switch actuator, a hollow base, a shaft having a cam portion at one end for actuating a switch, means on said base including an apertured plate spaced axially of the cam portion for mounting the shaft for rotation from a neutral position in opposite directions to first and second operating positions, restoring means on one side of said plate and effective in response to rotation of said shaft to said first position only and release of said shaft at said first position to return the shaft to said neutral position, said restoring means including a spring, and means for stressing said spring in response to rotation of said shaft to said first position and for preventing stressing of said spring in response to rotation of said shaft to said second position, and detent means on the other side of said plate including parts on said plate and on said cam portion in the space therebetween engageable to latch the shaft in said second position in response to rotation thereof to said second position.

2. An actuator as defined in claim 1 wherein said detent means includes a leaf spring on said plate having a projection, and an extension projecting from said cam portion to latchingly engage said projection when the shaft is rotated to said second position.

3. In a rotary switch actuator, support means, a shaft having a cam portion at one end for actuating a switch, mounting means on said support means mounting the shaft for rotation from a neutral position in opposite directions to first and second operating positions, a coil spring wrapped around the shaft, a pair of rings secured to opposite ends of said spring, means for effecting relative rotation between said rings to stress said spring in response to rotation of the shaft to said first position, and for effecting rotation of the rings as a unit to prevent stressing of said spring in response to rotation of the shaft to said second position, and detent means including a leaf spring on said mounting means and an extension on said cam portion engageable when said shaft is rotated to said second position to latch the shaft in said second position.

4. An actuator as defined in claim 3 wherein said leaf spring is generally fiat and includes a projection extending axially of said shaft, said extension projecting from said cam portion toward said projection.

5. An actuator as defined in claim 3 wherein said mounting means includes an apertured plate, said coil spring and said detent means being on opposite sides of said plate.

6. In a rotary switch actuator, support means, actuating means mounted by said support means for rotation from a neutral position in opposite directions to first and second operating positions, restoring means operatively engageable with said actuating means and effective in response to rotation of the actuating means to said first position only and release of said actuating means at said first position to return the actuating means to the neutral position, and detent means including parts on said support means and on said actuating means engageable to latch said actuating means at said second position in response relatively rotatable to extend the spring in response to rotation of the actuating means to said first position, and rotatable as a unit to prevent extension of the spring in response to rotation of the actuating means to said second position.

7. In a rotary switch actuator, support means, actuating means mounted by said support means for rotation from a neutral position in opposite directions to first and second operating positions, restoring means operatively engageable with said actuating means and effective in response to rotation of the actuating means to said first position only and release of said actuating means at said first position to return the actuating means to the neutral position, and detent means including parts on said support means and on said actuating means engageable to latch said actuating means only at said second position in response to rotation thereof to said second position, said detent means including a leaf spring on said support means, and an extension on said actuating means latchingly engageable with said leaf spring in response to rotation of said actuating means to said second position, said restoring means including a coil spring wrapped about said actuating means, and means connected to the ends of said spring relatively rotatable to extend the spring in response to rotation of the actuating means to said first position, and rotatable as a unit to prevent extension of the spring in response to rotation of the actuating means to said second position.

8. In a rotary switch actuator, a hollow base, a shaft having a cam portion at one end for actuating a switch, means on said base including an apertured plate spaced axially of the cam portion for mounting the shaft for rotation from a neutral position in opposite directions to first and second operating positions, restoring means surrounding said shaft and effective in response to rotation of said shaft to said first position only and release of said shaft at said first position to return the shaft to said neutral position, and detent means including parts on said plate and on said cam portion in the space therebetween engageable to latch the shaft in said second position in response to rotation thereof to said second position, said restoring means including a coil spring wrapped around said shaft, a pair of rings secured to opposite ends of said spring, and means for effecting relative rotation between said rings to stress said spring in response to rot-ation of the shaft to said first position, and for effecting rotation of the rings as a unit to prevent stressing of said spring in response to rotation of the shaft to said second posltion.

9. In a rotary switch actuator, support means, actuating means mounted by said support means for rotation from a neutral position in opposite directions to first and second operating positions, a coil spring wrapped about said actuating means, a pair of rotatable rings urrounding the actuating means and each having a hook secured to a separate end of said spring, said hooks being spaced angularly about the axis of rotation of the actuating mean-s relative to each other when the actuating means is in the neutral position, each ring having also a radially extending projection spaced angularly about the axis of the actuating means with respect to its associated hook, said projections also being spaced angularly about the actuating means with respect to each other when the actuating means is in the neutral position, the projection of one of said rings having a greater radial extent than the projection of the other of said rings, said support means having a ridge extending radially into the'path of rotation of the projection of said one of said rings and extending short of the path of rotation of the projection of said other of said rings, said actuating mean having an axially extending tab adapted for engagement with the projection of said other of said rings, said other of said rings being rotated by engagement of its projection by said tab in response to rotation of the actuating means 7 i I toward said first position away from :said neutralposition to stretchsaid spring while'said one ring is held against rotation-by engagement of its projection with said ridge, said tab being moved away from the projection of said other of said rings in response torotation of the actuating means toward said second position from said with said tab in response to rotation of the shafttoward said first position away from said neutral position to neutral position to prevent relative rotation of; said rings, and detent meansincluding parts on said support means and on said actuating means engageable to latch said actu- I ating means at said second. position in response to rota tion thereof to said second position.

10. In a rotary switch actuator, a hollow base, a shaft having a cam portion at oneend for actuating a switch,

means on said base including an apertured platespaced axially of the cam portion for mounting the shaft for rotation from aneutral position in opposite directions to first and second operating positions, a coil spring on stretch said spring while said one ring is held against rotation by engagement of its projection with said ridge, said tab being moved away from the projection of said other ,of-said ringsin-response' to rotation of the shaft toward said second position from said neutral position to prevent relative rotation of said rings, and detent means including cooperating parts engageable to latch the shaft in said second positioninresponse to rotation thereof to "said second position, one of'said cooperating parts being one sideof said plate wrapped around the shaft, apair of rot-atablerings on said one side of said plate surrounding the shaft and each having a hook secured to asepa' 735,077

rate end of said spring, sai-d hooks being spaced angularly aboutthe'axis of theshaft relative'to'each other when the shaft is in a neutral position, each ring having also a radially extending projection spaced angularly about the shaft axis with respect to its associated hook, said projections also being spaced angularlyabout the shaft axis with respect to each other when the'shaft is in said new tral position, the projection of one of said rings having a greater radial extent than the projection of the other of said rings, said base having a ridge extending radially into the path of rotation of the projection of said one of said'm'ngs and extending short of the path of rotation of/ ing an axially extending ta-b adapted for engagement with the projection of said other of said rings, said other of said rings being rotated by engagement ofits projection the projection of said other ofsaid rings, said shaft ha-V- fixed and the other cooperating partbeing rotatable with the shaft-relative; to the one cooperating part, both of said cooperating parts being positioneda'n the space mtween said plate and the cam portion on the other side of said plate. a

I References Cited by the Examiner UNITED .STATES PATENTS OTHER REFERENCES 1 IBM Technical DisclosureBulL, page 19, October 1960, vol. 3, No.5.

LBROUGHTON G. DURHAM, Primary Examiner. 

1. IN A ROTARY SWITCH ACTUATOR, A HOLLOW CASE, A SHAFT HAVING A CAM PORTION AT ONE END FOR ACTUATING A SWITCH, MEANS ON SAID BASE INCLUDING AN APERTURED PLATE SPACED AXIALY OF THE CAM PORTION FOR MOUNTING THE SHAFT FOR ROTATION FROM A NEUTRAL POSITION IN OPPOSITE DIRECTIONS TO FIRST AND SECOND OPERATING POSITIONS, RESTORING MEANS ON ONE SIDE OF SAID PLATE AND EFFECTIVE IN RESPONSE TO ROTATION ON SAID SHAFT TO SAID FIRST POSITION ONLY AND RELEASE OF SAID SHAFT AT SAID FIRST POSITION TO RETURN THE SHAFT TO SAID NEUTRAL POSITION, SAID RESTORING MEANS INCLUDING A SPRING, AND MEANS FOR STRESSING SAID SPRING IN RESPONSE TO ROTATION OF SAID SHAFT TO SAID FIRST POSITION AND FOR PREVENTING STRESSING OF SAID SPRING IN RESPONSE TO ROTATION OF SAID SHAFT TO SAID SECOND POSITION, AND DETENT MEANS ON THE OTHER SIDE OF SAID PLATE INCLUDING PARTS ON SAID PLATE AND ON SAID CAM PORTION IN THE SPACED THEREBETWEEN ENGAGEABLE TO LATCH THE SHAFT IN SAID SECOND POSITION IN RESPONSE TO ROTATION THEREOF TO SAID SECOND POSITION. 